So does anyone know of an iPhone app that will let me view forum posts from various forums (such as this one) as well as let me post replies?

I am asking because I mainly lurk in forums while on my iPad or iPhone, and sometimes it can be a real pain.

I tried one app that claimed to be able to compile subscribed threads from several forums for viewing, but it turned out that the forum owners would have to integrate a script into their forums (or something along those lines), which just sounded like a real pain.

There is an app named Tapatalk that I use for a couple of different forums.
It works very well. You can review unread posts or look at an entire thread. Very handy for when you are away from a computer.

I'm not sure what all is involved, I believe the site owners have to set some things up to make it work.